Standard output

https://docs.python.org/3/tutorial/inputoutput.html

https://docs.python.org/3/library/string.html

PRINT

# In Py2, 'print' is a statement.
# Expressions are converted to strings [str(expression) or repr(expression)].

print expression   # '\n' at the end
print expression, expression, expression   # separated by ' '
print expression,   # a comma, no '\n' at the end
print >> outfile, expression, expression   # print to an open file

# In Py3, 'print()' is a builtin function.
# print(*objects, sep=' ', end='\n', file=sys.stdout, flush=False)
# Print 'objects' to the text stream 'file', separated by 'sep' and followed by 'end'.
# 'sep', 'end', 'file' and 'flush', if present, must be given as keyword arguments.

print(expression)   # '\n' at the end
print(expression, expression, expression)   # separated by ' '
print(expression, expression, sep='|')   # separated by '|'
print(expression, end=' ')              # ' ' at the end
print(expression, expression, file=outfile)   # print to an open file

# Compatibility: print a single string.

print ( "{} {}".format(expression, expression) )

STR.FORMAT

# str.format(*args, **kwargs)
# Formatting {position}, {position:format_spec}.
# {position:10} type str, minimum width 10 chars [width]
# {position:4d} type int, minimum width 4 chars [width][type]
# {position:.3f} type float, 3 digits after a dot [.precision][type]
# {position:8.1f} type float, 1 digit after a dot, total width 8 chars [width][.precision][type]

"{0} or {1}".format(True, False)   # 'True or False'
"{} or {}".format(True, False)   # 'True or False', position may be omitted
"{1} or {0} and {1}".format(True, False)   # 'False or True and False'
"doubling {{ and }} {}".format(11)   # 'doubling { and } 11'

"pi is {0:.5f}".format(math.pi)   # 'pi is 3.14159'

# Using keywords.
# Formatting {key}, {key:format_spec}.

"{person} is {description}".format(person="Adam", description="funny")
"We obtained {result:d}".format(result=12)   # 'We obtained 12'

# Using conversion.
# '!a' applies ascii(), '!s' applies str(), and '!r' applies repr().
# Formatting {position!conversion}, {position!conversion:format_spec}.
# Formatting {key!conversion}, {key!conversion:format_spec}.

word = 'ą\tć'
"{0!s}|{0!r}|{0!a}".format(word)   # "ą\tć|'ą\\tć'|'\\u0105\\t\\u0107'"

# Using alignment options in format_spec.
# '<' forces the field to be left-aligned within the available space
# '>' forces the field to be right-aligned within the available space
# '^' forces the field to be centered within the available space
# '=' forces the padding to be placed after the sign (if any) 
#    but before the digits (‘+000000120’)

"|{0:>3}|{1:<3}|{2:^3}|{3:0=+5}|".format('a', 'b', 'c', 12)
# '|  a|b  | c |+0012|'   # [[fill]align][sign][width]

"{:*^20}".format("centered")   # use '*' as a fill char
# '******centered******'   # [[fill]align][width]

# Using an attribute name and an element index.
# Formatting {position.attr_name}, {position[idx]}.
# Formatting {key.attr_name}, {key[idx]}.

L = [11, 12, 13]
"{0[1]}".format(L)   # '12'
"{seq[2]}".format(seq=L)   # '13'

coord = (3, 5)
"x {0[0]}  y {0[1]}".format(coord)   # 'x 3 y 5'

p = Point(12, 34)
"{0.x}".format(p)   # '12'
"{point.y}".format(point=p)   # '34'

c = 2-4j
"complex {0} real {0.real} imag {0.imag}".format(c)
# 'complex (2-4j) real 2.0 imag -4.0'

# Using different bases.

"int: {0:d};  hex: {0:x};  oct: {0:o};  bin: {0:b}".format(42)
# 'int: 42;  hex: 2a;  oct: 52;  bin: 101010'

# with 0x, 0o, or 0b as prefix:
"int: {0:d};  hex: {0:#x};  oct: {0:#o};  bin: {0:#b}".format(42)
# 'int: 42;  hex: 0x2a;  oct: 0o52;  bin: 0b101010'

F-STRINGS

Formatted string literals (f-strings) begin a string with a prefix 'f' or 'F'.

# f"first {expression} second {expression}"
# F'single {expression}'

year = 2016
event = 'Referendum'
f'Results of the {year} {event}'   # 'Results of the 2016 Referendum'

# Using optional format specifiers {expression!conversion:format_spec}.

import math
f'pi is {math.pi:.3f}'   # 'pi is 3.141'

name, phone = 'Andrzej', 4628
f'|{name:10}|{phone:10d}|'   # '|Andrzej   |      4628|'
# Alignment options can be used.
f'|{name:>10}|{phone:<10}|'   # '|   Andrzej|4628      |'